Abstract
OBJECTIVE: Individuals with lumbar spinal stenosis due to osteoarthritis (LSS-OA) often have disc degeneration at multiple levels, as well as multiple symptomatic appendicular joints. These have received limited attention in this OA population. We documented the occurrence and investigated the influence of lumbar disc degeneration (LDD) and multijoint burden on postoperative outcome in LSS-OA. METHODS: Patients (n = 119) undergoing decompression surgery ± fusion for LSS-OA completed the Oswestry Disability Index (ODI) pre- and 12-months post-surgery. Pre-surgery patient factors: age, sex, education, BMI, smoking, comorbidities, depression, anxiety, and symptomatic appendicular joints. Disc grading was performed for each lumbar level; an overall LDD score was derived. Patients were categorized as group-1 (LDD score 0-6), group-2 (score 7-10), or group-3 (score 11+; greatest LDD burden). LDD and multijoint influence on 12-month post-surgery outcomes (ODI status score and percentage improvement) were examined using adjusted linear regression. RESULTS: Just over 19 % were LDD group-1, 55.5 % group-2, 25.2 % group-3. Individuals with greater LDD burden had more symptomatic appendicular joint sites. Mean 12-month ODI score and percentage improvement: group-1, 19.5 and 58.6 %; group-2, 20.0 and 52.2 %; group-3: 27.6 and 28.1 %. Regression analyses: percentage improvement was 21.5 points lower in group-3 vs. group-1, and 12-month score 10.7 units worse. Greater multijoint burden was also associated with less improvement (16.1 percentage-points lower for 3+ vs. 0-2 joints). CONCLUSIONS: One-quarter of this LSS-OA sample had high LDD burden; LDD burden was strongly associated with outcome. Findings suggest that understanding outcomes in this OA population requires multilevel spine burden and multi-appendicular joint burden consideration.